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1. Not bent
   "looking for an unbent nail"; "trees with straight unbent trunks make the best lumber"
    
2. Erect in posture
   - straight, unbowed

1. (of a person) stop bending, stand straight up
   - straighten
    
2. Unfasten, as a sail, from a spar or a stay
    
3. Free from flexure
   "unbend a bow"
    
4. Make less taut
   - relax
    
5. Rest from work; become less busy, tense or anxious
   - relax, loosen up, unwind, decompress, slow down
    
6. Release from mental strain, tension, or formality
   "unbend the mind from absorbing too much information"

See also: erect, straight, upright, vertical

Type of: change posture, change state, loose, loosen, loosen up, make relaxed, relax, straighten, straighten out, turn, unfasten, unlax, unstrain, unwind

Antonym: bend, twist